From 3dd9b226dc56b84761f413bfaf6af7bcb6c2d802 Mon Sep 17 00:00:00 2001
From: Profpatsch <mail@profpatsch.de>
Date: Tue, 11 Oct 2022 12:52:58 +0200
Subject: [PATCH] Action/Server: reverse the order of modules in showFroms

This will *not* change the top-link for the target to the first
module, just switch around the displayed list.

We need to push the logic out a bit further to change the top target.
---
 src/Action/Server.hs | 14 +++++++++++---
 1 file changed, 11 insertions(+), 3 deletions(-)

diff --git a/src/Action/Server.hs b/src/Action/Server.hs
index e99ef333..544d1c35 100644
--- a/src/Action/Server.hs
+++ b/src/Action/Server.hs
@@ -284,9 +284,17 @@ showFroms urlOpts allTargets = do
             -- each as links to either the package
             -- or the target inside the respective module.
             $ link pkgName pkgUrl
-              : [ link moduleName targetUrl
-                | (targetUrl, moduleName) <- targets
-                ]
+              :
+                -- quite peculiarly, the list of modules inside each package
+                -- is sorted in reverse-topological order, that is downstream
+                -- modules are first in the result. We want the declaration module
+                -- to be first, so we reverse the ordering.
+                -- *Why* the list is in reverse topological order is not quite
+                -- clear to the authors, there is a good chance it’s accidental.
+                reverse
+                    [ link moduleName targetUrl
+                    | (targetUrl, moduleName) <- targets
+                    ]
 
 showURL :: UrlOpts -> URL -> String
 showURL IsHaddockUrl x = "haddock/" ++ dropPrefix "file:///" x